CLM20-2 full issue-1 - Flipbook - Page 17
Measuring conservation success on farmland
The grassland fields created next to the brook
have been farmed at low intensity, with either a
single summer hay cut or mob-grazing by sheep.
Decisions on how to farm these grasslands are
made based on floristic diversity, the amount of
ragwort (high abundance means that the sward
cannot be used for hay) and the availability of
sheep from the local farming community (we
do not have in-house livestock). Our piecemeal
acquisition of land has included a string of small
fields alongside the brook, many of which are of
low agricultural value owing to the propensity
of the watercourse to flood. They have all been
converted to flower-rich grassland and now form a
wildlife corridor approximately 4km in length and
50–100m wide.
Non-farmed habitats include a mixture of
grassland, including the 6m margins around all
arable fields; hedgerows; small areas of scrub and
woodland; and planted trees along the brook.
Further enhancement of the brook has included
various restoration techniques, ranging from
reinstating historical meanders to combatting
invasive species. Much of the management work
on these habitats is undertaken by volunteer
groups, particularly the removal of Himalayan
balsam from the brook and hedge-laying of the
now mature hedgerows. With several kilometres
of new hedge, however, it is not possible for it
all to be laid by volunteers, and some sections
are managed by careful mechanical trimming.
In 2018 we hosted the National Hedge Laying
Championship, which resulted in 1km of superbly
laid hedge in five hours. The regrowth on this has
now thickened up. Some sections of veteran hedge
are left untrimmed, offering a further contrast; no
single style of hedge suits all wildlife.
Wildlife monitoring
Integral to the success of the farm – and
particularly for demonstrating this success to
other farmers – has been a long history of wildlife
recording, ranging from casual observation
to long-term standardised annual monitoring
of various taxonomic groups. Most of this
monitoring work has been undertaken by
volunteers, including the first decade which was
entirely volunteer led.
One of the biggest regrets is that no surveys of
the ’98 Land were carried out before restoration
began. The first surveys were conducted in
1999, by which time the basic features, cropping
regimes and less-intensive techniques had had a
year to take effect. Nonetheless, positive results
have been seen from a wide range of taxa,
including rare arable plants, meadow flora,
butterflies and bumblebees, amphibians, reptiles
and various mammals, including bats, which
have increased dramatically over the meadows,
and otters and water voles, which have returned
to the brook. Water voles have benefitted from
a campaign to eradicate American mink from
watercourses in the region.
The most comprehensive monitoring has been
of birdlife. The BTO Common Bird Census
(CBC) technique has been repeated annually,
showing a gradual increase in bird numbers
and in particular strong rises in Red-listed
farmland birds such as grey partridge, skylark
and yellowhammer. Some of these species have
declined slightly since the loss of 10% set-aside
in 2008, but numbers remain above the 1999
baseline, and it is likely that the populations from
that baseline were already above average for the
area. As hedgerows have matured, other species
have started to increase, most notably the Amberlisted dunnock and wren.
The CBC is the gold standard for territory
numbers but requires a large amount of work.
It was developed in the 1960s (Williamson
& Homes 1964) and formed the basis of
bird monitoring for many years but has been
superseded by the Breeding Bird Survey (BBS),
which was introduced in 1994 (Field & Gregory
1999). This survey involves volunteers walking
transects through a random 1km grid square
(around 3,000 squares are covered in total) on
two dates during spring. A simple total of birds
counted is used to establish the index value for
each square, and the totals gathered from around
the country are compiled to generate trends
for nearly 120 regularly occurring species of
breeding bird.
In 2015, the charity Redlist Revival (RLR)
developed a method of generating bird data for
areas of land that could be directly compared
with the BBS dataset, allowing landowners to
benchmark their performance against national
standards. Instead of random 1km grid squares,
communities can choose transect lines that
Conservation Land Management Summer 2022 | Vol. 20 No. 2 15
